In the lead-up to the release of the last US soldier to be held prisoner by the Taliban in Afghanistan, 54-year-old Bob Bergdahl talked to the Guardian's Sean Smith about his feelings following his son's capture

Sean Smith spent a month embedded with The US Army's 501st Parachute Regiment in June this year. With inadequate vehicles, relations with Afghan security forces at a standstill and the constant threat of IEDs, the soldiers are losing heart for a fight they feel their presence is only prolonging

As Afghanistan prepares for an election, award-winning photographer Sean Smith, stationed with British troops during Operation Panther's Claw, finds many soldiers becoming frustrated at the inexperience and lack of discipline of the Afghan National Army